Radiology is the medical discipline that uses medical imaging to diagnose and treat diseases within us.
A variety of imaging techniques such as X-ray radiography, ultrasound, computed tomography (CT), nuclear medicine including positron emission tomography (PET), fluoroscopy, and magnetic resonance imaging (MRI) are used to diagnose or treat diseases. Interventional radiology is the performance of usually minimally invasive medical procedures with the guidance of imaging technologies such as those mentioned above.

Bone densitometry, also called dual-energy x-ray absorptiometry, DEXA or DXA, uses a very small dose of ionizing radiation to produce pictures of the inside of the body (usually the lower (or lumbar) spine and hips) to measure bone loss. It is commonly used to diagnose osteoporosis, to assess an individual's risk for developing osteoporotic fractures. DXA is simple, quick and noninvasive. It's also the most commonly used and the most standard method for diagnosing osteoporosis.
This exam requires little to no special preparation. Tell your doctor and the technologist if there is a possibility you are pregnant or if you recently had a barium exam or received an injection of contrast material for a CT or radioisotope scan. Leave jewelry at home and wear loose, comfortable clothing. You may be asked to wear a gown. You should not take calcium supplements for at least 24 hours before your exam.
Breast imaging is a test that uses a tracer and special camera to find breast cancer. Rather than simply taking a picture of a breast, molecular breast imaging is a type of functional imaging. This means that the pictures it creates show differences in the activity of the tissue.
A computerized tomography (CT) scan combines a series of X-ray images taken from different angles around your body and uses computer processing to create cross-sectional images (slices) of the bones, blood vessels and soft tissues inside your body. CT scan images provide more-detailed information than plain X-rays do.
An echocardiogram (echo) is a graphic outline of the heart's movement. During an echo test, ultrasound (high-frequency sound waves) from a hand-held wand placed on your chest provides pictures of the heart's valves and chambers and helps the sonographer evaluate the pumping action of the heart.
Magnetic Resonance Imaging (MRI) is a non-invasive imaging technology that produces three-dimensional detailed anatomical images. It is often used for disease detection, diagnosis, and treatment monitoring. It is based on sophisticated technology that excites and detects the change in the direction of the rotational axis of protons found in the water that makes up living tissues.